X-ray emission by multiple passes of electrons through periodic and crystalline targets mounted inside a synchrotron

The number of passes of high-energy electrons through multiple foil and crystal radiators mounted inside of the Tomsk "Sirius" synchrotron, and the resulting increase in x-ray production efficiencies from these radiators, have been measured. The influence of electron transmission on the spectral and spatial distributions of parametric x radiation and on the spatial distribution of transition radiation has also been observed. We find that multiple passes increase the yields of these sources without destroying their angular distributions and spectra. Thus, multiple passes of electrons through these novel radiators may make them useful as x-ray sources for scientific and industrial purposes.